WebMD reports researchers tracked more than 1,200 couples for 10 years. They found wives who cared for husbands with dementia were four times more likely to develop the condition themselves. Husband caregivers were nearly 12 times more likely to develop dementia.

Although dementia isn't contagious, a psychiatrist at New York University says the amount of stress in caring for a spouse with dementia is high, and stress is a known risk factor for dementia.